Whelp, this may not be a popular opinion, but after hundreds upon hundreds of uses under my belt with a 4 piece Santa Cruz Shredder, 2 piece Space Case, 4 piece unbranded generic grinder, a credit card grater, and 2 piece plastic pyramid tooth shredder....well...I found that they all work and perform to the the same degree. All operate smoothly when freshly cleaned, but get gunked up over use. Shred/grind/cut quality varies upon very, very close inspection but all vape equally well by my estimation and observation in Pax, Volcano, and SSV (based on effect from said herb as well as overall ABV consistency, take from that as you will).
Were I to go back and purchase my first grinder there are only two main criteria that I feel are relevant to me now: capacity and whether I want a kief screen or not. I got the CC shredder to help prepare herb for the MFLB when I had it but once that vape was out of my rotation I haven't found the need for a particular herb grind. It's nice to try all the different models out there, and my SCS turns and shreds more effortlessly than my unbranded grinder, but was it really worth the extra money? Nah, not for my uses. Just felt this may be worthwhile to anyone on the fence about getting a new grinder.